Microprocessors are frequently used on their own or as part of microcontrollers that also include additional periphery on the chip such as network interfaces, ADC, DAC, I/O etc. in addition to the microprocessor.
Modern microprocessors as they are used in control units of motor vehicles, for instance (e.g., in engine control devices for the engine control) are most often multicore processors having multiple (at least two) processor cores. A processor core includes an arithmetic logic unit (ALU), which represents the actual electronic arithmetic unit for the execution of tasks, programs, arithmetic instructions etc., and furthermore a local memory. Such a local memory may be developed as a register set made up of one or multiple register(s) or as a RAM, for example. In addition, the microprocessor includes a global memory which can be developed as flash memory, NOR-flash or RAM, for instance.
Program code that is to be executed by a microprocessor is often encoded in a special instruction-set architecture of the microprocessor.
A command set architecture describes the instruction set of a microprocessor, i.e., the quantity of instructions that can be executed by the microprocessor, as well as the binary coding of the instruction set. The instruction-set architecture may also describe data types and the set-up of data structures, a memory architecture and the addressing of memory areas. Furthermore, special behavior types of the microprocessor, e.g., the manner in which it responds to an interrupt request, are able to be described by the instruction-set architecture.